Conventionally, a DPF regeneration control device starts the execution of automatic DPF regeneration processing based on the fact that the accumulation estimation value of PM accumulated on a DPF has reached the start value of the automatic DPF regeneration processing so that the temperature of an exhaust gas passing through the DPF is raised by an automatic DPF regeneration device and the PM accumulated on the DPF is incinerated and removed by the heat of the exhaust gas. Furthermore, the DPF regeneration control device starts cancel processing for canceling the execution of the automatic DPF regeneration processing based on the prohibition manipulation of the automatic DPF regeneration processing although the DPF satisfies a condition that the automatic DPF regeneration processing is executed.
In accordance with this type of an exhaust treatment device, there are advantages in that the DPF may be repeatedly used by the automatic DPF regeneration processing and the automatic DPF regeneration processing may be cancelled by the cancel manipulation of a regeneration cancel manipulation device under the condition that it is not appropriate to execute the automatic DPF regeneration processing.
However, the prior art is problematic in that the cancel state of the automatic DPF regeneration processing cannot be freely released.